how does cpo work

[lovethesport]

i have a 04 x5 which now under cpo warranty...

i hear some odd noises in the front suspension almost as if the shocks are rattling or something else has gone loose....

lets say , i take the vehicle in----what will i be charged for if the dealer finds no fault----

2nd: what will i be charged for if they find something wrong with a part not covered by cpo and i would like to get that item fixed at a independant shop......

thank you